What does the lo character on the screen of formaldehyde detector mean?

LO is usually the abbreviation of "lowvoltage", which means low voltage. The lo character appears on the screen of the formaldehyde detector. It is necessary to check the sensor connector to see if it is in poor contact or the line end is broken, or replace the battery.

In alkaline solution, the reducing ability is stronger. Can burn, steam and air form an explosive mixture, and the explosion limit is 7%-73% (volume). The ignition point is around 300℃.

It can be prepared by dehydrogenation or oxidation of methanol under the catalysis of metals such as silver and copper, and can also be separated from oxidation products of hydrocarbons. It can be used as raw materials for phenolic resin, urea-formaldehyde resin, vinylon, urotropine, pentaerythritol, dyes, pesticides and disinfectants.

Extended data:

Colorless aqueous solution or gas, with irritating smell. Soluble in water and ether, the highest concentration of aqueous solution can reach 55%, and the pH value is 2.8~4.0. Can be mixed with water, ethanol, acetone and other organic solvents in any proportion. Liquid is easy to be turbid when it is stored for a long time in cold, and paraformaldehyde precipitates at low temperature.

Some formaldehyde escapes during evaporation, but most of it becomes trioxymethylene. This product is a strong reducing agent, which is more reducing when it is slightly alkaline. It can be slowly oxidized into formic acid in air.

Anhydrous formaldehyde can be obtained by direct dehydrogenation of methanol, and hydrogen is also produced by-product. This method is an attractive method to prepare formaldehyde. The key to its progress lies in the improvement of catalyst performance.

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